Energy recovery in electrically powered vehicles

ABSTRACT

An electrically powered vehicle is disclosed, having a resistor to facilitate dynamic breaking when the electrically powered vehicle is moving downhill or under other external motive force.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application Ser. No. 62/441,847, filed Jan. 3, 2017 and entitled “Energy Recovery in Electrically Powered Vehicles.”

TECHNICAL FIELD

The subject matter described herein relates to energy recovery and, in particular, to energy recovery in electrically powered vehicles.

BACKGROUND

Skateboards typically include an elongated board, sometimes referred to as a deck, having an upper surface and a lower surface. The upper surface typically support the feet of a rider of the skateboard and the lower surface typically have two trucks attached to the deck disposed toward either end of the deck. The upper surface may support the rider who is sitting on the skateboard. The trucks typically include one or more axles. Wheels, typically one on either side of the truck, attach to the axles. The trucks typically provide several degrees of freedom to the wheels relative to the skateboard deck, allowing the wheels to roll over uneven ground and facilitate turning of the skateboard by the rider.

Skateboards typically require the rider to provide the propelling force to move the skateboard, usually by the rider having one foot on the deck of the skateboard and another pushing off from the ground.

Some skateboards have been developed that include a power source. The power source may be a gasoline powered engine. The power source may be an electrically-powered motor. When going downhill on a powered skateboard it can be desirable to slow down in order to control the descent.

SUMMARY

A regenerative braking system and method is provided for an electrically powered vehicle. In one aspect, the electrically powered vehicle includes one or more electrical motors configured to provide motive force to a powered wheel of the electrically powered vehicle. The one or more electrical motors can be configured to generate electricity when the electrically powered vehicle is moved by a force external to the electrically powered vehicle. The electrically powered vehicle further includes a battery configured to provide electrical power to the one or more electrical motors. The electrically powered vehicle further includes a resistor configured to receive electrical power and heat to generate a load. The electrically powered vehicle further includes a controller configured to determine that the one or more electrical motors are generating electricity. The controller further configured to divert electricity to (a) the battery in response to an indication that the battery has not satisfied a charging threshold and (b) the resistor in response to an indication that the battery has satisfied the charging threshold.

In another aspect, a method of regenerative braking is provided. The method includes providing, by one or more electrical motors, motive force to a powered wheel of the electrically powered vehicle. The method further includes generating, by the one or more electrical motors, electricity when the electrically powered vehicle is moved by a force external to the electrically powered vehicle. The method further includes providing, by a battery, electrical power to the one or more electrical motors. The method further includes receiving, by a resistor, electrical power and heat to generate a load. The method further includes determining that the one or more electrical motors are generating electricity. The method further includes diverting electricity to (a) the battery in response to an indication that the battery has not satisfied a charging threshold and (b) the resistor in response to an indication that the battery has satisfied the charging threshold.

The details of one or more variations of the subject matter described herein are set forth in the accompanying drawings and the description below. Other features and advantages of the subject matter described herein will be apparent from the description and drawings, and from the claims. Certain features of the currently disclosed subject matter are described for illustrative purposes only and it should be readily understood that such features are not intended to be limiting. The claims that follow this disclosure are intended to define the scope of the protected subject matter.

DESCRIPTION OF DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, show certain aspects of the subject matter disclosed herein and, together with the description, help explain some of the principles associated with the disclosed implementations. In the drawings:

FIG. 1 is a schematic view of various elements of the skateboard, having one or more features consistent with implementations of the current subject matter;

FIG. 2 is a schematic illustration of an example of a powered wheel and a portion of the skateboard, having one or more elements consistent with the current subject matter;

FIG. 3 is a schematic view of various elements of a powered skateboard, having one or more features consistent with implementations of the current subject matter;

FIG. 4 is an illustration of a powered skateboard, having one or more features consistent with implementations of the current subject matter;

FIG. 5 is a schematic illustration of a circuit diagram having one or more features consistent with implementations of the current subject matter;

FIG. 6 is a schematic illustration of a circuit diagram having one or more features consistent with implementations of the current subject matter;

FIG. 7 is an illustration of an electrically powered vehicle having a dynamic load resistor in accordance with one or more features consistent with implementations of the current subject matter;

FIG. 8 is an illustration of an electrically powered vehicle having a dynamic load resistor in accordance with one or more features consistent with implementations of the current subject matter; and

FIG. 9 is an illustration of a process flow diagram having one or more features consistent with implementations of the current subject matter.

When practical, similar reference numbers denote similar structures, features, or elements.

DETAILED DESCRIPTION

When an electrically powered vehicle having one or more electrical motors to power it travels downhill, or is moved by some other force, the electrical motors act as generators and create electricity. When a load is applied to the motor(s) when they are generating electricity, the load can cause the motor(s) to retard the motion of the electrically powered vehicle. This phenomenon can be referred to as regenerative breaking. The load can come in the form of a battery being charged by the electricity generated by the motor(s). The load can come from a resistor being heated by the electricity generated by the motor(s).

This description, at times, referred to an electrically powered skateboard to demonstrate the application of the invention. This is for ease of explanation only and is intended to be limiting. An electrically powered skateboard is one example of an application of the present description. The presently described regenerative braking system can be applied to any electrically powered vehicle. FIG. 1 is a schematic view of various elements of the skateboard 100, having one or more features consistent with implementations of the current subject matter. The skateboard 100 can comprise a skateboard deck 102. The skateboard deck 102 may comprise a bottom portion 104. The bottom portion 104 may have truck-mounting portions 106 configured to facilitate engagement with one or more skateboard trucks 108. The skateboard deck 102 may comprise a top portion 110. The top portion 110 may have an upper surface 112. The upper surface 112 may be configured to support a rider of the skateboard 100.

The one or more skateboard trucks 108 can be configured to support one or more wheels 114 and 116. In some variations, the skateboard trucks 108 may be configured to support unpowered wheels 114 and/or powered wheels 116. The powered wheels 116 can be disposed on both front and rear trucks 108 of the skateboard 100, or can be disposed on just one of the trucks 108. The powered wheels 116 can be disposed on one side or on both sides of the truck(s) 108. The powered wheels 116 can be disposed on the truck 108 that is located on the rear portion of the skateboard 100.

FIG. 2 is a schematic illustration of an example of a powered wheel 116 and a portion of the skateboard 100, having one or more elements consistent with the current subject matter. The powered wheel 116 can include an electric motor disposed within the powered wheel 116. The electric motor can include a rotor 117 and a stator 119. The rotor 117 and the stator 119 can be engaged with the axle 118 of the skateboard truck 108. The electric motor can be a three-phase electric motor. The electric motor can be a five-phase electric motor. The electric motor can be an n-phase electric motor. The powered wheel 116 can be attached to a truck 108 on a truck axle 118. The truck axle 118 can include a flange 120. The flange 120 can be configured to prohibit inward movement of the powered wheel 116. The flange can include an outer rim 122. The outer rim 122 can be configured to support an internal surface 124 of the powered wheel 116. The outer rim 122 providing support for the powered wheel 116, reducing strain on the internal components of the powered wheel 116 and the axle 118. The axle 118 can include an engagement portion 126. The engagement portion 126 can be configured to provide a surface on which the force of the powered wheel 116 can work against. Without having an engagement portion 126, the powered wheel 116 would spin about the axle 118 and provide little motive force. The axle 118 can include a retaining slot 128, configured to facilitate retaining the powered wheel 116 on the axle 118.

The powered wheel 116 can include a first bearing 130. The first bearing 130 can be configured to engage with the flange 120. The first bearing 130 can have an inner race 132 configured to engage with the surface 122 of the flange 120. The first bearing 130 can have an outer race 134 configured to engage with the inner surface 124 of a wheel 134. The inner race 132 and outer race 134 of the first bearing 130 can be rotationally engaged. Rotational capabilities of the first bearing 130 can be facilitated through the use of ball bearings, greased channels, oil channels and/or other friction reducing mechanisms between the inner race 132 and the outer race 134. In this manner, the first bearing 130 can be configured to facilitate rotation of the powered wheel 116 about the axle 118.

In some variations, the first bearing 130 can be disposed within a first rotor side 138. The first rotor side 138 can include an inner surface 140. The first rotor side 138 can comprise a center bore 140 fixedly attached to the outer race 134 of the first bearing 130. The first rotor side 138 can be a solid rotor. The first rotor side 138 can further comprise hollows bored into the inside perimeter. In some variations, the first rotor side 138 can include between 6 and 20 hollows bored into the inside perimeter. The hollows can be configured to provide airflow, reduced weight, and structural integrity. The hollows can be covered to prevent ingress of foreign bodies into the rotor. The first rotor side 138 can be visible when the powered wheel 116 is assembled. The second rotor side 144 can include a single large bore in its center adapted to fixedly attach to the outer race 156 of the second bearing 154 disposed in the center of the second rotor side 144.

The outer race 134 of the first bearing 130 can be configured to engage with the inner surface 140 of the first rotor side 138. In some variations, the first bearing 130 can have an inner diameter of between 5 mm and 10 mm. The first bearing 130 can have an outer diameter between 15 mm and 30 mm. The first bearing 130 can have a thickness between 5 mm and 10 mm. One of ordinary skill in the art will understand and appreciate that the size of the bearing is proportionate to the size of the powered wheel 116. Consequently, the presently described subject matter contemplates different sizes of first bearing 130, just as it contemplates different sizes of powered wheels 116.

The powered wheel 116 can include a rotor can 142. The rotor can 142 can comprise a material having one or more magnetic properties. The rotor can 142 can be comprised of a magnetically permeable material. The rotor can 142 can be configured to cause all or most of the magnetic field to be contained within the rotor 117. The rotor can 142 can comprise a single piece of steel alloy. The rotor can 142 can be configured to engage with at least a portion of a first rotor side 138 and a second rotor side 144. The first rotor side 138 and the second rotor side 144 can comprise one or more teeth 146. The teeth 146 can be configured to receive and support magnets 148. The teeth 146 can be configured to support the magnets 148 at specific locations. Magnets 148 can be permanent magnets. The first rotor side 138 and the second rotor side 144 can include flanges between 1 mm and 2 mm in length extending inward. In the preferred embodiment, the first rotor side 138 and the second rotor side 144 can be made of aluminum. In an alternative embodiment, the first rotor side 138 and the second rotor side 144 can be identical.

The magnets 148 can be arranged into a magnet array. Between 10 and 28 rectangular magnets 148 can be positioned within the rotor can 142. The magnets 148 can be neodymium magnets. The magnets 148 can be disposed in a circular array forming a ring. The magnets 148 can be attached to the inside of the rotor can 142 by an adhesive such as epoxy. The outer ends of the magnets 148 can lock into the teeth, or pockets 146 of the first rotor side 138 and the second rotor side 144.

The stator 119 can be configured to be disposed within the rotor 117. The stator 119 can be formed of a permanent magnet. The stator 119 can be formed of an electromagnet. The stator 119 can be formed of laminated steel. The stator 119 can comprise stator slots 150 and stator teeth 152. The stator slots 150 and stator teeth 152 can be disposed about the periphery of the stator 119. In some variations, the stator 119 can comprise a plurality of steel sheets stacked together in a circular array. The steel sheets can be fixedly attached to the axle 118. The stacks of steel sheets can form stator teeth 152. The stator slots 150 and stator teeth 152 can be configured to carry electric wire forming windings (not shown). The windings can be three-phase, five-phase, or n-phase windings. The windings can be wound copper wire. The windings can be a solid metal. The windings can be some other suitable material. The windings can be configured to carry current. A controller can be configured to cause the current to pass through successive phases of the electric motor to cause the rotor 117 to rotate about the stator 119.

A second bearing 154 can be configured to be disposed between the axle 118 and the inner surface of the stator 117. The second bearing 154 is rotationally attached to the axle 118 of the skateboard truck 108 on its inner race 158 and allows the powered wheel 116 to spin on the axle 118 by reducing rotational friction. The second bearing 154 is positioned within the inside of the stator 119 and allows the stator to spin around the outer race 156 of the second bearing 154. One of ordinary skill in the art will appreciate and understand that the size of the second bearing 154 depends on the size of the powered wheel 116 and/or the axle 118. The present disclosure contemplates different sizes of powered wheels 116 and axles 118. Consequently, the present disclosure contemplates different sizes of second bearing 154. The first bearing 130 and the second bearing 154 can be configured to facilitate rotation of the rotor 117 about the stator 119 that is fixedly engaged to the axle 118. The stator 119 can be fixedly engaged to the axle 118 by having an internal surface 152 with a shape that compliments the shape of the axle 118. The stator 119 can be held in place by a stator pin, mechanical locking groove, a circlip, or the like. The shape of the internal surface 152 can include a flat portion that compliments with the flat portion 126 of the axle 118.

The powered wheel 116 can comprise a wheel 136 configured to fit over the rotor 117. The wheel 136 can be glued or molded around the rotor 117. The wheel 136 can include an internal structure facilitating the engagement of the wheel 136 with the rotor 142. The wheel 126 can be press-fit onto the rotor 142. In some variations, the wheel 136 may be thermo cooled. The wheel 136 can serve as a tire for the powered wheel 116. The wheel 136 can be configured to mechanically engage with the rotor 117. The wheel 136 can be composed of polyurethane. The wheel 136 can be composed of rubber or any similar compound or material used for similar purposes.

In some variations, the powered wheel 116 can include wheel sizes ranging from 25 mm to 100 mm in diameter and from 25 mm to 100 mm in width.

One or more Hall effect sensors 160 can be positioned between the teeth 152 of the stator 119. The Hall effect sensor(s) 160 can be positioned at specific locations. The Hall effect sensor(s) 160 can be attached between the stator teeth of the stator 119 with adhesive. In some variations, the Hall effect sensor(s) 160 can be attached to a printed circuit board disposed between the teeth of stator teeth. The Hall effect sensor(s) 160 can be attached to the stator 119 mechanically. In some variations, the teeth 152 of the stator 119 can include pockets configured to receive the Hall effect sensor(s) 160. The hall effect sensor(s) 160 can be configured to facilitate a smooth start of the electric motor from a stationary position.

The Hall effect sensor(s) 160 can function by operating as a transducer and changing the amount of voltage it releases in relation to a magnetic field to achieve different mechanical effects. The Hall effect sensor(s) 160 can be configured to provide information about the position of the rotor to a controller. With this information, the controller can more accurately control the flow of current to the various phases of the electric motor.

Wiring to connect the windings about the stator teeth 152 to a power source and/or a controller can be disposed along the flat portion 126 of the axle 118. The wiring can be run through an aperture 162 through the flange 120 of the axle 118.

FIG. 3 is a schematic view of various elements of the skateboard deck 102, having one or more features consistent with implementations of the current subject matter. The skateboard deck 102 may comprise a bottom portion 104. The bottom portion 104 may have truck mounting portions 106 configured to facilitate engagement with one or more skateboard trucks 108 (as shown in FIG. 1).

The skateboard truck(s) 108 can be made from aluminum. The skateboard truck(s) 108 can comprise an axle 118 that extends horizontally from one wheel to the other wheel. The skateboard truck(s) 108 can comprise multiple axles that extend outward from the skateboard truck(s) 108 on either side of the skateboard truck(s) 108. Each skateboard truck can be configured to have each wheel positioned between about 120 mm and about 180 mm apart. The skateboard truck(s) 108 can be mechanically attached to the skateboard by bolts.

The skateboard deck 102 may comprise a top portion 110. The top portion 110 may have an upper surface 112. The upper surface 112 may be configured to support a rider of the powered skateboard 100. The skateboard deck 102 may have a cavity 170. The cavity 170 may be disposed between the bottom portion 104 and the top portion 110 of the skateboard deck 102. The cavity 170 may be adapted to store one or more components of the powered skateboard 100.

The top portion 110 of the skateboard deck 102 may include an aperture 172. The aperture 172 may be configured to facilitate access to the cavity 170 between the top portion 110 and the bottom portion 104 of the skateboard deck 102.

The bottom portion 104 of the skateboard deck 102 may include support structures. The top portion 110 of the skateboard 102 may include support structures 174. The support structures may be configured to provide support for the top portion 110 of the skateboard deck 102 to facilitate the top portion 110 to support a rider of the powered skateboard 100. The support structure can be configured as a honeycomb structure. The support structure can include one or more lateral and/or longitudinal support structures.

In some variations of the current subject matter, the top portion 110 of the skateboard deck 102 may comprise multiple apertures 172, 176. One aperture 172 may be configured to facilitate access to components of the powered skateboard 100 that may be regularly removed. Such regularly removed components may include a fuel source for the powered skateboard 100 and/or a container for the fuel source of the powered skateboard 100. Another aperture 176 may be configured to facilitate access to components of the powered skateboard 100 that are not regularly removed. Such components not regularly removed may be control systems for controlling the powered skateboard.

The components may include a transceiver 620 (as shown in FIG. 6) configured to communicate with one or more mobile devices. The transceiver 620 may be one or more of a Wi-Fi transceiver, a Bluetooth transceiver, a Near-Field-Communication transceiver, a sub-gigahertz transceiver, and/or any other wireless communication transceiver. The transceiver 620 may be in electronic communication with the control system for the powered skateboard. The control system may be configured to modify one or more parameters of the powered skateboard.

A lid 178 can be provided for the aperture 172. The lid 178 can be configured to cover the aperture 172 and provide support to a rider of the powered skateboard 100. The lid 178 can be configured to be screwed in place to cover the aperture 172 and provide support to the rider. The lid 178 can be configured to attach to the top portion 110 of the skateboard deck 102 via a hinge, a latch, a connector, or any other connection mechanism. The top portion 110 of the skateboard deck 102 can comprise slots to engage with the lid 178, such that the lid 178 can slide into the slots and cover the aperture 172 and support the rider. The lid 178 may be removable engaged with the top portion 110 of the skateboard deck 102.

Having the lid 172 removably engaged with the top portion 110 of the skateboard deck 102 can facilitate a user of the powered skateboard to access one or more components of the powered skateboard stored in the cavity 170. For example, the powered skateboard may be electrically powered. The cavity 170 can be configured to store one or more battery packs to provide electrical power to one or more electric motors of the powered skateboard. Having the lid 178 removably engaged with the top portion 110 of the skateboard deck 102 can facilitate a user to exchange a spent battery pack with a charged battery pack. A user may, therefore, be able to continue using the powered skateboard.

In variations where the skateboard deck 102 includes multiple apertures 172, 176, the aperture 176 for providing access to non-regularly removed components of the powered skateboard 100 may be covered by a lid 180. The lid 180 for covering aperture 176 can be secured such that the lid 180 is not easily removed, and may withstand a tumbling of the skateboard or any other shock. The lid 180 for covering aperture 176 can be secured to the top portion 110 of the skateboard deck 102 using screws, adhesive, and/or other securing methods.

The skateboard deck 102 can include one or more conduits 182. The one or more conduits 182 may be configured to facilitate connections between the power source and the motive source for the powered skateboard 100. The one or more conduits 182 can be configured to facilitate connections between an electrical power source disposed in the cavity 170 of the skateboard deck 102 and one or more electric motors disposed outside of the cavity 170 of the skateboard deck 102.

The components stored in the cavity 170 between the top portion 110 and the bottom portion 104 of the skateboard deck 102 may include a receiver, transmitter, and/or transceiver, herein referred to as a transceiver. The transceiver may be adapted to receive instructions from a user to control the powered skateboard 100. Instructions may be received from a transmitter. The transmitter may include a hand-held transmitter (such as shown in FIG. 12).

The skateboard deck 102 can include a port aperture 184. The port aperture 184 can be configured to secure an electronic port 186 into the skateboard deck 102. The electronic port 186 can be one or more of a USB port, a FireWire port, and/or other electronic port. The electronic port 186 can be configured to facilitate communications between an external device and one or more components of the powered skateboard 100. The electronic port 186 can be configured to facilitate transfer of electrical energy to one or more components of the powered skateboard 102. The electronic port 186 may be configured to facilitate transfer of electrical energy from one or more components of the powered skateboard to an external device.

FIG. 4 is a schematic view of various elements of a powered skateboard 100, having one or more features consistent with implementations of the current subject matter. The top portion 110 of the skateboard deck 102 may be secured to the bottom portion 104 of the skateboard deck 102. The top portion 110 of the skateboard deck 102 may be secured to the bottom portion 104 of the skateboard deck 102 by one or more of screws, adhesive, welding, mechanically fastening, and/or other securing mechanism. The top portion 110 of the skateboard deck 102 may be contiguous with the bottom portion 104 of the skateboard deck 102. The skateboard deck 102 may have a monocoque structure.

The skateboard deck 102 may comprise injection molded plastic. The skateboard deck 102 may comprise thermoplastic. The skateboard deck 102 may comprise carbon fiber. The skateboard deck 102 may comprise forged carbon fiber. The skateboard deck 102 may comprise pre-preg carbon fiber.

The components of the skateboard deck 102 may have a modular structure. The modular structure may have a polygonal structure. The polygonal structure may be hexagonal or rectangular. The polygonal structure may provide a lightweight structure while maintain strength and stability of the components of the skateboard deck 102.

FIG. 5 is a schematic diagram of an energy capture system 500 for a personal transportation device, having one or more features consistent with the present description. The energy capture system 500 can be configured to capture kinetic energy generated from a potential energy of a personal transportation device. For example, when a personal transportation device is at the top of a hill it has a potential energy, due to the force of gravity, that will pull the personal transportation device to the bottom of the hill. For example, if the personal transportation device is a skateboard, to slow down, a rider of the skateboard would have to create friction to dissipate the kinetic energy of the skateboard. The rider can create friction by performing a manual to scrape the back edge of the board on the ground, or drag a foot to create friction and slow the board and the rider. The energy capture system 500 of FIG. 5 can be configured to capture the kinetic energy of a personal transportation device moving downhill and cause the personal transportation device to slow down.

The energy capture system 500 can be configured to convert the kinetic energy of the downhill-moving personal transportation device into heat and/or chemical energy. A personal transportation device can include one or more motors 502 attached to one or more wheels of the personal transportation device. When the personal transportation device is coasting downhill, the wheel(s) will cause the rotor of the motor(s) 502 to rotate about the stator of the motor(s) 502. This will create an electrical charge. The electrical charge can be diverted by a controller 504. The controller 504 can be configured to divert the electrical charge to a battery 506 and/or to a resistor 508.

When the battery 506 has below a threshold charge level the controller 504 can be configured to divert electrical energy generated by the motor(s) 502, when the personal transportation device is travelling downhill and/or coasting. Power from the battery 506 can be used to drive the motor(s) 502 when the personal transportation device needs to be moved under load.

When the battery 506 is above a threshold charge level, electrical energy produced by the motor(s) 502 cannot be stored by the battery 506. In such situations, the controller 504 can be configured to divert the electrical energy produced by the motor(s) 502 to the resistor 508. The resistor 508 can be one or more of a dynamic load resistor, a flex circuit, metal, a conductive material, or the like. The resistor 508 can be configured to be heated by the electrical energy produced by the motor(s) 502. The heat can then dissipate into the atmosphere.

Charging the battery 506 and/or diverting electrical energy to the resistor 508 can facilitate downhill braking of the personal transportation device. In some aspects, by causing the energy capture system 500 to apply a load to the motors 502. In some implementations, the controller 504 can determine an amount of the load and/or from which source the load should come from to retard the motion of the personal transportation device. For example, the controller 504 can be configured to select the source of the load based on a charging level of the battery 506 and/or a level and/or rate of electrical energy being received from the motor(s) 502. In some aspects, in response to capturing energy created by the rotation of the rotor about the stator of the motor(s) 502, the controller 504 can be configured to increase or decrease the amount of load (e.g., level of resistance in resistor 508, friction of rotation of rotors, etc.) and thus increase or decrease the amount of electrical energy generated and diverted to the battery 506 and/or the resistor 508.

In some implementations, the rider of the personal transportation device may be able to control an amount of braking through the use of a hand-held controller in communication with the personal transportation device. For example, the hand-held controller may be an application on a mobile device, the mobile device, or a dedicated hand-held controller of the personal transportation device. In other aspects, the personal transportation device may comprise an input (e.g., brake lever or button) for the user to indicate a desired amount of braking. In some implementations, the rider and indicate an amount of braking on the hand-held controller and the hand-held controller can communicate with the controller 504 to adjust the amount of braking via the motors 502.

When the battery 506 is being charged, by the electrical energy produced by the motor(s) 502, the amount of energy produced by the motor(s) 502 may exceed the rate at which the battery 506 can be charged. When this occurs, the controller 504 can be configured to detect the excess amount and/or rate of electrical energy being produced and divert at least a portion of the electrical energy to the resistor 508. Diverting at least a portion of the electrical energy to the resistor 508 can avoid a voltage spike that may harm the electrical components of the personal transportation device.

In some variations, the resistor 508 can be configured to perform one or more functions of an inductive charging pick-up node. A charging conductor 510 can be provided that is configured to provide power wirelessly through inductive power transfer. When the resistor 508, capable of performing the functions of an inductive charging pick-up node, is placed in proximity of the charging conductor 510, electrical energy can be transferred from the charging conductor 510 to the resistor 508.

In some variations, energy from the inductive charging can be routed through the control unit 504 to the battery 506, as illustrated in FIG. 5. In other variations, as shown in FIG. 6, the energy from the inductive charging can be routed directly from the resistor 608 to the battery 606.

The resistor can be formed from a flex circuit, metal, other conductive material, or the like. Having a dynamic load resistor, such as dynamic load resistor 508 illustrated in FIG. 5, allows for downhill breaking even when the battery 506 is fully charged. Without the dynamic load resistor 508, when an electrically powered vehicle is going downhill, the motor(s) 502 can act as generators creating electrical energy from the downhill movement, caused by gravity, of the electrically powered vehicle. This energy can be diverted, by the control unit 504 to the battery 506, charging the battery 506. However, when the battery 506 satisfies the charging threshold and/or is fully charged, the energy generated by the motor(s) 502 cannot be diverted to the battery 506. As a result, there is no longer a load on the motor(s) 502 and the motor(s) 502 cease their deceleration function for the electrically powered vehicle.

With the resistor 508 in electronic communication with the motor(s) 502, as well as the battery 506, the resistor 508 can receive the electrical charge generated by the motor(s) 502 when the electrically powered vehicle is moving downhill. The resistor 508 will apply a load on the motor(s) 502, receive electrical charge and heat. This heat can be dissipated into the atmosphere.

FIG. 7 illustrates a resistor 702 disposed in an electrically powered vehicle 704, the resistor 702 having one or more features consistent with the present description. In some variations, where an electrically powered vehicle 704 includes a battery well 706, the resistor 702 can be disposed within the battery well 706.

FIG. 8 illustrates a resistor 802 disposed in an electrically powered vehicle 804, the resistor 802 having one or more features consistent with the present description. In some variations, the resistor 802 can be disposed on a surface of the electrically powered vehicle 804. For example, the resistor 802 can be disposed on an underside surface 806 of the electrically powered vehicle 804. Disposing the resistor 802 on the underside surface 806 of the electrically powered vehicle 804 can increase the ability of the resistor 802 to cool after heating due to absorbing energy from dynamic breaking of the electrically powered vehicle 804.

FIG. 9 is a process flow diagram illustrating a process 900 having one or more features consistent with the present description.

At 902, an acceleration of an electrically powered vehicle can be detected. A determination that the acceleration is due an an external force can be made. The acceleration, of the electrically powered vehicle, can cause one or more motors of the electrically powered vehicle to generate electricity.

At 904, using a controller and in response to an indication that a battery of the electrically powered vehicle is not fully charged, the electricity generated by the one or more motors can be diverted to the battery to charge the battery.

At 906, using a controller and in response to an indication that a battery of the electrically powered vehicle is fully charged, the electricity generated by the one or more motors can be diverted to a resistor.

The subject matter described herein can be embodied in systems, apparatus, methods, and/or articles depending on the desired configuration. The implementations set forth in the foregoing description do not represent all implementations consistent with the subject matter described herein. Instead, they are merely some examples consistent with aspects related to the described subject matter. Although a few variations have been described in detail above, other modifications or additions are possible. In particular, further features and/or variations can be provided in addition to those set forth herein. For example, the implementations described above can be directed to various combinations and subcombinations of the disclosed features and/or combinations and subcombinations of several further features disclosed above. In addition, the logic flows depicted in the accompanying figures and/or described herein do not necessarily require the particular order shown, or sequential order, to achieve desirable results. Other implementations may be within the scope of the following claims. 

What is claimed is:
 1. An electrically powered vehicle, comprising: one or more electrical motors configured to provide motive force to a powered wheel of the electrically powered vehicle, the one or more electrical motors configured to generate electricity when the electrically powered vehicle is moved by a force external to the electrically powered vehicle; a battery configured to provide electrical power to the one or more electrical motors; a resistor configured to receive electrical power and heat to generate a load; and a controller configured to determine that the one or more electrical motors are generating electricity and to divert electricity to (a) the battery in response to an indication that the battery has not satisfied a charging threshold and (b) the resistor in response to an indication that the battery has satisfied the charging threshold.
 2. The electrically powered vehicle in accordance with claim 1, wherein the resistor is coupled with the powered wheel of the electrically powered vehicle.
 3. The electrically powered vehicle in accordance with claim 2, wherein the resistor provides the load from the received electrical power to the powered wheel of the electrically powered vehicle.
 4. The electrically powered vehicle in accordance with claim 3, wherein the resistor providing the load is based on a determination by the controller.
 5. The electrically powered vehicle in accordance with claim 1, wherein the powered wheel includes a stator motor.
 6. The electrically powered vehicle in accordance with claim 1, wherein the controller is further configured to adjust an amount of the generated electricity from the one or more electrical motors.
 7. The electrically powered vehicle in accordance with claim 1, wherein the controller is further configured to: determine that a rate of electrical energy diverted to the battery satisfies an energy rate threshold for the battery; and divert the generated electricity to the resistor in response to the rate satisfying the energy rate threshold.
 8. The electrically powered vehicle in accordance with claim 1, wherein the controller is further configured to adjust an amount of braking of the electrically powered vehicle in response to an input from a wireless device.
 9. The electrically powered vehicle in accordance with claim 1, wherein the resistor is further configured to receive inductive energy from a charging conductor.
 10. The electrically powered vehicle in accordance with claim 9, wherein the resistor is further configured to provide the received inductive energy to the controller, the controller further configured to provide the received inductive energy to the battery.
 11. A method of regenerative braking for an electrically powered vehicle comprising: providing, by one or more electrical motors, motive force to a powered wheel of the electrically powered vehicle; generating, by the one or more electrical motors, electricity when the electrically powered vehicle is moved by a force external to the electrically powered vehicle; providing, by a battery, electrical power to the one or more electrical motors; receiving, by a resistor, electrical power and heat to generate a load; determining that the one or more electrical motors are generating electricity; and diverting electricity to (a) the battery in response to an indication that the battery has not satisfied a charging threshold and (b) the resistor in response to an indication that the battery has satisfied the charging threshold.
 12. The method of claim 11, wherein the resistor is coupled with the powered wheel of the electrically powered vehicle.
 13. The method of claim 12, wherein the resistor provides the load from the received electrical power to the powered wheel of the electrically powered vehicle.
 14. The method of claim 13, wherein the resistor providing the load is based on a determination by the controller.
 15. The method of claim 11, wherein the powered wheel includes a stator motor.
 16. The method of claim 11, further comprising adjusting an amount of the generated electricity from the one or more electrical motors.
 17. The method of claim 11, further comprising: determining that a rate of electrical energy diverted to the battery satisfies an energy rate threshold for the battery; and diverting the generated electricity to the resistor in response to the rate satisfying the energy rate threshold.
 18. The method of claim 11, further comprising adjusting an amount of braking of the electrically powered vehicle in response to an input from a wireless device
 19. The method of claim 11, further comprising receiving, at the resistor, inductive energy from a charging conductor.
 20. The method of claim 19, further comprising: providing the received inductive energy to a controller coupled to the resistor; and providing, by the controller, the received inductive energy to the battery. 